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BisonWare Multiple Vulnerabilities

Multiple vulnerabilities in the BisonWare FTP Server can cause denials of service.

The vulnerabilities are:

The server fails to close the socket created by a PASV command in multiple PASV commands are executed back to back. This can create a socket and memory shortage that will not be fixed when the client disconnects from the server.

Connecting to the server and issuing a "PORT a" command followed by several thousand carriege returns and new lines will cause the server to crash.

The are multiple buffer overflows in all commands that take arguments. For example LIST and CWD both crash the server if they are passed string longer than 1500 characters.

The USER command in conjunction with a password, each containing a string over 550 characters long, is vulnerable as well which means an attacker doesn't need to logon to the server to exploit the vulnerability.